1. Field of the Invention
The present invention relates to a heat-blocking glass which is applied to the windshield of a vehicle or to a windowpane of a building so as to decrease the cooling load of the cooling system thereof by inhibiting the penetration of heat rays into the interior thereof.
2. Description of the Prior Art
One type of conventional heat-blocking glass comprises a multi-layer interference film as a heat-blocking film, the interference film being coated on a glass substrate. In general, conventional heat-blocking glass does not effectively block heat rays since its range of reflection of the wave-length of heat rays is narrow. To widen the range of reflection, the number of layers of the film must be increased, thereby increasing the cost thereof.
Another type of conventional heat-blocking glass comprises a multi-layer interference film coated on one side of the glass substrate and an infrared rays-blocking film coated on the other side of the glass substrate so as to enhance the blocking of heat rays. However, this heat-blocking glass involves a problem in that visible rays are reflected by the infrared rays-blocking film. In order to eliminate this problem, one or more anti-reflection films must be coated on the infrared rays-blocking film, thereby increasing the cost thereof.